primero
first
primary
first in importance
+
-ero
adjective suffix
Primero means first and can be thought of as primary0 (first in importance0) + -ero1 (adjective suffix1).
adjective
- firstFirst in order or importanceÉl fue el primero en llegar a la fiesta. // He was the first to arrive at the party.
noun
- first oneThe first oneEl primero en la fila recibirá un premio. // The first one in line will receive a prize.